larger garter snakes wanted

Wanted: any larger garter snake or any other species that is known to eat mice. I had a large one living under my house that kept the mice out, but the landscapers accidentally killed it with a mower. I now have mice again. I'd like get one and introduce it to the area where the old one was doing so well. If you have snakes and kids, put them to work catching them, I'll pay $5ea for the largest you can find up to three.